Abstract: Objective: To explore the effect of a probiotic compound preparation composed of Bifidobacterium longum BB536 and Bifidobacterium lactis HN019 on dysbiosis of murine gut microbiota induced by ceftriaxone sodium. Methods: Ceftriaxone sodium (2 mg/g) was given to mice for 5 days to construct intestinal flora dysbiosis model mice and then they were randomly divided into model group, low-dose (2×10⁵ CFU/g), medium-dose (4×10⁵ CFU/g) and high-dose (1.2×10⁶ CFU/g) groups of probiotic compound preparations. In addition, normal mice were set as the control group. From the 6th day, each dose group was administered with the corresponding dose of probiotic compound preparation, the control group and model group were administered with equal volume of normal saline for 30 days. After the gavage, the mice feces were collected to count the intestinal flora and 16S rDNA high-throughput sequencing was performed to analyze the diversity and structure of the flora. The levels of IL-2, IL-6, IL-1β and TNF-α in serum were measured. The contents of MDA, T-SOD, GSH and GSH-PX in the jejunum and liver were measured. Results: After administration of ceftriaxone sodium, the levels of IL-2, IL-6, IL-1β and TNF-α in serum showed an upward trend, the level of MDA in the jejunum increased significantly (P<0.05) and the level of T-SOD decreased significantly (P<0.05). After the intervention of high-dose probiotic compound preparation, the levels of IL-6 and IL-1β were significantly decreased (P<0.05), the levels of IL-2 and TNF-α were significantly decreased (P<0.01). In addition, the levels of MDA in the jejunum and liver were significantly decreased, the level of T-SOD was significantly increased (P<0.05), the level of GSH-PX was significantly increased (P<0.01) and the level of GSH in the jejunum was significantly increased (P<0.01). In terms of intestinal microbes, the number of Enterococci and Enterobacteria in the feces decreased, while the number of Lactobacilli and Bifidobacteria increased when the probiotic compound preparation was administered after antibiotic injury compared with that before the probiotic compound preparation was administered. The results of microbial diversity analysis showed that the microbial richness of each dose group was restored compared with the model group, and the predicted intestinal function of the middle-dose and high-dose groups was closer to that of the control group. Conclusion: The probiotic compound preparation can promote the production of antioxidants, reduce the level of cytokines, promote the reproduction of beneficial bacteria, increase the abundance of intestinal flora and improve the intestinal flora imbalance caused by ceftriaxone sodium.